Process for sterilizing filter masses



May 1, 1934. KJENZINGER 13 E ;PROCESS FOR STERILIZING FILTER MA'SSES Filed Nov. 50, 1952 7 Fig.1

3 4 1 4 7 Fig.4 7 Z l E- 1\ DMD L J 6 Q49 F W 7 I Fig.5

Arm/me? iEDsTA'rEs PATENT OFFICE v PRQCESS FOR STERILIZING FILTER MASSES I KiirlEnzinger, Heidelberg, Germany, assignor to Enzinger Union Werke' Aktiengcsellschaft, lfcddersheim, Germany Application November 30, 1932, Serial No. 645,081 in Germany December 22, 1931 '1 Claim. 01. 210-177) In .the use of filters employing compressed output is raised because owing to the shorter cakes of fibrous filter pulp or filter mass, which washing period the machine is .sooner free for find extensive employment for instance for milk, fresh washings. beer, wine and water, the soiled, paste clogged To enable'the filter mass to be sterilized in the filter cakes are cleansed in known manner after filter itself, an arrangement is advantageous removal from the filter cases by loosening in a which is characterized by the filter being in comfilter mass washing machine and treatment with munication with circulating or single flow means wat r. for a disinfecting agent, which can however be The mode of operation of such a machine and of the most diverse kind. I

10 the cleansing process therein are generally By way of example six arrangements of appaknown; mention will only be made of the fact ratus vfor carrying out the process according to that mechanical cleansing, sterilization of the the invention are diagrammatically illustrated in filter mass by heat and finally cooling all take the accompanying drawing. p a in the machine. The preparation of the Figures 1 to 3 are similar diagrammatic views filter cakes then takes place outside the machine showing three diiferent arrangements using by a press; the filter case is then charged with closed circuit circulation. the pressed Cakes and the filter n lly pressed Figures l and 5 showtwo further arrangements together to Close The fi te nOW ready for using open circuit through flow of the sterilizing use is filled with water and waits until put into agent, and v 20 service again. i Figured is a side elevation of a, similar arrange- 1 This mode of Operation a the va a ment to Figures 2 but with the heat exchanger above all that the wa h d and steriliz d mass aft r and circulating device combined with the filter being put into the filteris no longer sterile; this frame, 1 1

is because the cooling of the mass after steriliza- I 11 the figures 1 is the filter.

tion is efi'ected with water which is not sterile,v I Figure 1 the inlet and outletof the filter l aus t press tm t cannot be fi d are connected by a. pipe line 2 in which is included in sterile conditions, and because the filter itself a, pump 3. A funnel and cock 5 are also provided,

is not Ste ile and the Stands for a long p riod. by which a disinfecting agent can be introduced for instance over night, under ordinary noni t th pipe,

sterile main water. The mode of operation is as follows:

In the process according to the invention the After th filt r layers or cakes have been put echa ca cleansing of the filter mass, that i into the filter, the latter screwed together and the Was Out Of th muddy Particles and the made ready for service, the cock 5 is opened and like is still effected in the washing machine with di m tam; poured i through th funnel 4, The warm Water u t the tflowi Water is Clear; cock is thereupon closed and the disinfectant cirh P ep of the filter cakes and-their culated by the pump 3, flowing in the direction of sertion in the filter cases then take place without th arr w, throughth filter d ba k t th previous sterilization of the mass in the washing suction side of the pump; in this way th i t; n'i'aohine being necessary. After pressing tois closed. During the driving of the disinfectant gether the cases, the filter is ready for service through the filter 1' all the internal parts which and sterilization of the completed filter and the later come into contact with the actual liquid to mass therein now takes place for example by he filtered are rendered germ freeblowing through steam, gases or the like, why When the sterilization is complete the pipe washing through disinfecting liquid for instance line 2 is unscrewed from the filter 1 and the latter 45 chlorinated water 'or ozonized water or the like. co p to the line for the liquid to be fi t ed. For better utilization of the disinfecting agent, Figure 2 illustrates a Similar pparatus. The it can be circulated in closed circuit. The filter difference compa d With i u 1 s at aheater can then be put into operation in sterile condi- 6 with steam supply 7 and condensate oflt-ake 8, tion. which can also be used as a cooler, is provided;

50 The process according to the invention not only in this way the sterilizing agent, for example results in a sterile'filter but there is also a conwater, can be brought to sterilizing temperature siderable saving in water, steam and time. Since and immediately after sterilization cooled again,

the washing machine is only in operation during indirectly that is by heat exchange and without v the period of mechanical washing and ofpressing mixing of the heating or cooling medium with 55 of the cakes, there is a saving of power while the the circulating liquid.

Figure 3 shows a similar arrangement to Figures 1 and 2. Here a container 9 for the disinfectant is provided which is connected by pipe 1o with a known mixing device 11 by which the disinfectant is introduced into the pipe line 2. Either gaseous or liquid disinfectants can be admixed as may be desired.

In Figure 4 a filter is shown in which instead of closed circuit circulation by pump as is provided in Figures 1-3, open circuit through flow of disinfectant through the filter 1 is employed. If sterilization is effected for instance with water, the water which enters at 12 is raised to sterilization temperature by the heater 6 which has a heating agent supply 7 and oiftake 8, for instance by the action of steam, and is driven through the filter. Subsequent cooling can then be efiected in a suitable manner.

Figure 5 shows a similar arrangement to Figure .4, also operating an open circuit. In place of the heater of Figure 4, a container 9 for disinfecting is here provided, which is connected with a mixing device 11 in the water pipe 12 by a pipe 10, in similar manner to the arrangement of Figure 3. Y

In the arrangements of Figures 1-5 both the circulating means and the heat exchanger are arranged outside the filter frame. It has been found advantageous to arrange these devices, or at least one of them in particular the heat exchanger, within the filter.

If the heat exchanger is within the filter its principal radiating surfaces are made usable for heating the filter contents and there remains a relatively small edge as a waste radiating surface g'vlng low radiation loss. A further advantage is that the production of the heat exchanger is simplified because it can be made of the same form as the filter and can be mounted in the filter frame. A considerable saving of space and simplification of control and maintenance are advantages of this arrangement.

The mounting of the circulating apparatus, that is of the pump and connecting pipes, on the filter frame reduces pipe lengths to the minimum whereby heat losses are avoided and an arrangement always ready for use and easy to supervise is produced.

The arrangement of the heat exchanger and circulating apparatus outside the filter, as in Figures 1-5 will advantageously be used where severalfilters in a single works are to be treated by the process according to the invention. The

ea ers heat exchanger and the circulating apparatus can for this purpose be transportably mounted on a common platform and be provided with con= nection pieces and pipes for the particular filter to be treated.

In Figure 5 a transportably cased filter is shown in which both the circulating apparatus and the heat exchanger are combined with the filter frame. Such filters are extensively used for example for the filtration of beer and the like.

At one end of the filter is the inlet connection 13 for the entry of the liquid to be filtered. Further the sight lantern 1a and cock 15 are provided in the usual way. At the opposite end of the filter is the outflow cook 15.

If the completely assembled filter in which the filter plates, cakes or the like have been placed, is to be sterilized, the filter is first filled with water. pump 18 by which the liquid is circulated is mounted upon the filter frame. The heat exchanger is marked 19; it is supplied for example with steam. To simplify the drawing, the connections for this purpose are omitted. The sterilizing agent, in the present case water, follows the path indicated by the arrows, being driven through pipe 20 into the heat exchanger 19 and there raised to sterilizing temperature. The water leaves the exchanger 19 through pipe 21 and with the three way cook 22 suitably set, passes through the end 23 of the filter and is distributed throughout the interior thereof. The sterilizing agent leaves the filter at the other end through the connection 24 and with the three way cook 25 suitably set passes into the pipe 26 which carries it in the direction of the arrow to the suction side of the pump.

It is pointed out that Figure 6 is only an example of the direct combination of the filter with the circulating apparatus and heat exchanger.

What I claim is:

A process for cleansing and sterilizing filter presses charged with fibrous filter mass which consists in cleansing the mass mechanically outside the filter press, forming it into cakesand charging the filter press therewith and sterilizing the cakes within the filter press by passing a fluid. medium not having inherent sterilizing properties but raised to sterilizing temperature therethrough in closed circuit, and then cooling the cakes by cooling said medium and continuing to circulate it.

KARL ENZINGER.

The inlet therefor is at 17. The i 

